NICOLA Sturgeon has warned she is "increasingly concerned" about the prospect of a No-Deal Brexit - and cannot give assurances the NHS won't face disruption in the weeks ahead as it continues to fight the Covid-19 pandemic.

The First Minister was speaking hours after a deadline was set for Sunday for the two sides to reach an agreement on a new trade arrangement.

If talks fail then the UK will leave the Brexit transition period on December 31 on a No-Deal basis.

"I can't stand here and give an absolute assurance that there will be no impact on our economy, on society and even on the health service if there is a No-Deal Brexit at the end of this year," she told Holyrood in response to a question from the Scottish Greens co leader Patrick Harvie at First Minister's Questions.

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She told MSPs the Scottish Government was "doing everthing in its powers to mitigate" against the impact of a No-Deal.

She added: "For example in relation to medical contingency planning we have been putting in place contingency plans that involve a national stockpile in intensive care and end of life medicines and we are continuing to build that stockpile."

She went on to say that the UK was also doing work to ensure a continuing supply of the Covid-19 vaccine from January 1.

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And she warned: "We are doing everything we can but nobody should be under illusions as to how deeply damaging the end of the transition is going to be - whatever the circumstances but how particularly it's going to be if there is no deal agreed."

Responding to Harvie warned of a "perfect storm" of Brexit, the pandemic and the extra winter pressures on the NHS.

Responding to the Greens MSP, the First Minister said: "I am deeply and increasingly concerned at the lack of clarity about the arrangements that will apply by the end of the Brexit transition period in just a matter of weeks' time."

Earlier Tesco said it was stock piling food supplies as it feared a No-Deal Brexit.

On Tuesday the Scottish Government announced that work is being undertaken to secure medical supplies.